The Norway rat is a moderately large, robust, grayish or brownish rodent with coarse fur and a long, sparsely haired, scaly tail. (3) The size and weight is variable, 3-21 oz. Males slightly heavier than females. The length is up to 12 in. (2)
Description:
They live about 1-2 years, very few live past 1 year.
The liter size is about 6-11, it really all depends on how big the mother is. They have up to 5 liters per year. Mating is all throughout the year. (2)
They tend to eat any species smaller then themselves such as reptiles, small birds, bird eggs, freshwater and intertidal species. They eat food crops and spoil human food stores by urinating and defecating in them. (1) Prefers foods rich in starch, but will pretty much eat anything.
Habitat and Distribution:
They're native to Japan and possibly the eastern mainland of Asia. (3) They've spread to all continents except for Antartica. (They're normally found nearly everywhere humans have settled) (3)
Impacts:
The ecological and human impacts are mostly negative, they seem to restrict the regeneration of many plant species by eating seeds or seedlings. They pretty much anything they get in contact with, being smaller species then themselves (also stated in diet section.) (1)
These rats, along with one of it's relatives the black rat, have been known to spread different diseases such as bacteria that causes the bubonic plague via fleas in certain areas of the world. Economic damage is caused by the rats chewing through different power cables. (1)
History:
They're thought to have arrived here in North America on ships in 1775 and have since, spread all over. (3)
Control Measures:
Elimination through trapping is used often, although it proves to be uneffective for the most part. It fails to remove all individuals. The use of anticoagulant poisons is the most common method of control. (1)
Norway (Brown) Rat
Scientific Name: Rattus NorvegicusGeneral Information:
The Norway rat is a moderately large, robust, grayish or brownish rodent with coarse fur and a long, sparsely haired, scaly tail. (3) The size and weight is variable, 3-21 oz. Males slightly heavier than females. The length is up to 12 in. (2)Description:
They live about 1-2 years, very few live past 1 year.The liter size is about 6-11, it really all depends on how big the mother is. They have up to 5 liters per year. Mating is all throughout the year. (2)
They tend to eat any species smaller then themselves such as reptiles, small birds, bird eggs, freshwater and intertidal species. They eat food crops and spoil human food stores by urinating and defecating in them. (1) Prefers foods rich in starch, but will pretty much eat anything.
Habitat and Distribution:
They're native to Japan and possibly the eastern mainland of Asia. (3) They've spread to all continents except for Antartica. (They're normally found nearly everywhere humans have settled) (3)Impacts:
The ecological and human impacts are mostly negative, they seem to restrict the regeneration of many plant species by eating seeds or seedlings. They pretty much anything they get in contact with, being smaller species then themselves (also stated in diet section.) (1)These rats, along with one of it's relatives the black rat, have been known to spread different diseases such as bacteria that causes the bubonic plague via fleas in certain areas of the world. Economic damage is caused by the rats chewing through different power cables. (1)
History:
They're thought to have arrived here in North America on ships in 1775 and have since, spread all over. (3)Control Measures:
Elimination through trapping is used often, although it proves to be uneffective for the most part. It fails to remove all individuals. The use of anticoagulant poisons is the most common method of control. (1)Works Cited:
Global Invasive Species. 20 Nov. 2008 <http://www.issg.org/database/species/ecology.asp?si=159&fr=1&sts=&lang=EN>. (1)
Wonderclub. 20 Nov. 2008 <http://www.wonderclub.com/Wildlife/mammals/
brown_rat.html>. (2)
Rattus norvegicus (Berkenhout). 20 Nov. 2008 <http://www.discoverlife.org/nh/
tx/Vertebrata/Mammalia/Muridae/Rattus/norvegicus/>. (3)